Final answer:
The Whig Party collapsed in 1856 due to a division within the party regarding the issue of slavery.
Step-by-step explanation:
The Whig Party collapsed in 1856 due to a division within the party regarding the issue of slavery. The party was deeply divided between Northern Whigs who opposed slavery and Southern Whigs who supported it. This division became more pronounced as tensions over slavery grew, leading to the party's eventual demise.
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